But the technique can be life-threatening, is not pain-free and has no advantage over other methods, a new study of 106 patients found.

The study, the most rigorous to date on the method, showed that patients' withdrawal was as severe as those of addicts undergoing other detox approaches.

"Anyone who tells you it's painless can only honestly be referring to the period the person is under anesthesia," said co-author Dr. Eric Collins of Columbia University Medical Center.

The study appears in Wednesday's Journal of the American Medical Association.

Patients, all heroin addicts, were divided into three treatment groups. Those receiving ultra rapid detox were anesthetized for about four hours while they got a large dose of a drug that blocks the brain's opioid receptors.

In an awake patient, the initial dose would cause severe withdrawal symptoms, Collins said. The anesthesia is meant to mask the symptoms.

Patients underwent withdrawal when they awoke, even though they were given additional medications for withdrawal symptoms that included anxiety, insomnia, achy muscles and joints, diarrhea and vomiting.

"People think this is a nice, pleasant way to sleep through the misery of opiate detoxification," said Dr. Susan Stine, who trains addiction psychiatry residents at Wayne State University School of Medicine and was not involved in the new study. "This is research that's been needed for some time."

The method also struck out on keeping addicts clean. Eighty percent of the anesthesia patients dropped out of follow-up treatment, a dropout rate slightly higher than for another method in the study.

Since it began about 15 years ago, the method has been linked with several deaths. In one case, New Jersey regulators fined and gave two-year license suspensions to two doctors practicing the method, although the doctors were cleared of negligence in seven deaths.

"Some doctors have put their financial interests way ahead of the well-being of their patients," said Dr. Thomas Kosten, professor of psychiatry at Yale University School of Medicine. He recommended maintenance methods such as methadone or buprenorphine, instead of detox, for narcotics addiction.

But methadone and buprenorphine create physical dependence and they must be tapered gradually to avoid withdrawal symptoms, or continued indefinitely.

Some people will choose detox because they reject exchanging one drug for another, said Jake Epperly, who runs ultra rapid detox programs in Chicago and Los Angeles.

"We've had no problems," Epperly said, adding that the JAMA study used a different ultra rapid detox method than his programs use.

The American Society of Addiction Medicine's policy statement on ultra rapid detox says the method should be paired with counseling services and should be done only by trained staff with access to emergency medical equipment. The group also said patients should be informed of risks and benefits of the method compared with other options.

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